镀锌中锰钢电阻点焊接头裂纹形态及分布.pdfVIP

2023年第52卷第17期热加工工艺ISSN1001-3814

Vol.52No.172023HotWorkingTechnologyCN61-1133/TG

接头裂纹形态及分布[J].

引用格式：孙福文，赵杨洋，王武荣，等.镀锌中锰钢电阻点焊

DOl:10.14158/ki.1001-3814

http:/riggy@

镀锌中锰钢电阻点焊接头裂纹形态及分布

孙福文，赵杨洋，王武荣，韦习成

(上海大学材料科学与工程学院，上海200444)

摘要：采用光学显微镜、扫描电镜附带能谱仪（EDS）、电子背散射衍射仪（EBSD），对镀锌中锰钢电阻点焊接头横

截面裂纹的形貌、分布及元素成分进行了研究。结果表明，88.1%的微裂纹分布在压痕台阶处，87.5%的裂纹为深度小于

50μm的浅裂纹；裂纹内部充满了锌且裂纹为沿晶裂纹，推断焊点表面裂纹属于液态金属脆化裂纹，点焊过程中镀锌层

受热熔化，沿钢材表面晶界渗入并在应力作用下产生沿晶开裂。

关键词：镀锌中锰钢；电阻点焊；液态金属脆化裂纹

中图分类号：TG453+.9文献标识码：A

MorphologyandDistributionofCracksinGalvanizedMediumManganeseSteel

ResistanceSpotWeldedJoint

SUNFuwen,ZHAOYangyang,WANGWurong,WEIXicheng

(SchoolofMaterialsScienceandEngineering,ShanghaiUniversity,Shanghai200444,China)

Abstract:Themorphology,distributionandelementcompositionofcracksincross-sectionofresistancespotwelding

jointofthegalvanizedmediummanganesesteelwerestudiedbyopticalmicroscopeandscanningelectronmicroscopy(SEM)

withenergydispersivespectrometersystem(EDS)andelectronbackscatteredscatteringdetection(EBSD).Theresultshowthat

88.1%ofthecracksarelocatedattheindentationslop,and87.5%%ofthecracksaresuperficialcrackswithadepthofless

than50μm;zincaccumulationoccursinthecracks,andthecracksareintergranularcracks.Itisinferredthatthecracks

belongtotheliquidmetalembrittlementcrack,aszinccoatingismeltedandpenetratesalongthegrainboundaries,

intergranularcrackoccursunderstress.

Keywords:galvaniz